The present invention relates to a gas production apparatus. Specifically, the present invention relates to a gas production apparatus that produces hydrogen and oxygen by decomposing water by receiving light.
In the prior art, as one of the modes of using solar light energy as a renewable energy, hydrogen production apparatuses have been suggested which produce hydrogen used for fuel cells and the like by using a photoelectric conversion material used for solar cells and utilizing electrons and holes obtained by photoelectric conversion for a decomposition reaction of water (for example, see JP 2012-177160 A and JP 2004-197167 A).
In both of the hydrogen production apparatuses disclosed in JP 2012-177160 A and JP 2004-197167 A, a photoelectric conversion portion or a solar cell, in which two or more PN junctions generating an electromotive force when solar light is incident thereon are connected to each other in series, is provided; an electrolytic solution chamber is disposed at the lower side of the photoelectric conversion portion or the solar cell that is opposite to a light receiving surface which receives solar light on the upper side of the photoelectric conversion portion or the solar cell; and the inside of an electrolysis chamber is divided by an ion-conductive partition or diaphragm, and the documents disclose that by the electric power that is generated in the photoelectric conversion portion or the solar cell by the received solar light, water is electrolyzed, and hydrogen is generated.
According to JP 2012-177160 A, because the hydrogen production apparatus can also adjust the orientation of the light receiving surface with respect to the solar light, the amount of incident light that will be subjected to photoelectric conversion can be increased, and hydrogen generation efficiency is not reduced.
Furthermore, according to JP 2004-197167 A, because the hydrogen production apparatus electrolyzes water by using electrode plates, which are connected to a p-type semiconductor and an n-type semiconductor of the solar cell, as a positive electrode and a negative electrode respectively, the efficiency of conversion of solar energy into hydrogen can be improved.